The first comprehensive analysis of normative oral glucose tolerance data using essentially the National Diabetes Data Group recommended glucose dose has been competed. For simplicity, NDDG recommended 75g for all adults regardless of body size; we have used 40 g/m2 surface area (our average BLSA male receives close to 80 g and our average BLSA female receives closer to 70 g). There is a progressive decrease in tolerance with age, the mean glucose levels being very similar to those of the larger glucose load test, but significantly lower. A new nomogram has been constructed which provides rapid age-adjusted evaluation of performance for men and for women. Theres is a significant sex difference; women have the better glucose tolerance. In addition to the two oral glucose tolerance tests, there has now been a 20 year follow-up of men given three other tests: IVGTT, cortisone GTT, and tolbutamide response test. Performances on all these tests are being compared by converting the usual interpretative scores (decay constants, glucose levels, and percent falls in glucose) into Z-scores. Effects of performance levels at different ages are being analyzed on serum lipid levels, blood pressure, and the development of overt diabetes, coronary artery disease, and on mortality.